Couplers for stackable platforms

ABSTRACT

The invention is an improved coupler for interconnecting a plurality of stackable platforms, the coupler having projections appropriately sized and spaced to facilitate frictional engagement of the coupler with platforms having different dimensions.

FIELD OF THE INVENTION

This invention relates to coupling elements used to removably secure aplurality of platforms in stackable juxtaposition. More specifically,the invention relates to couplers capable of removably connectingplatform sections having different dimensions.

BACKGROUND OF THE INVENTION

In many industrial and commercial work environments, workers areprovided with flooring surfaces which provide separation between theunderlying flooring and the worker's feet. Such flooring providesthermal insulation, improves footing, and separates the worker's feetfrom contaminants, fluids, or moisture which may be found on the factoryor workplace floor.

Often, this type of flooring is in the form of individual andrepositionable panels which may be laid in the tiled fashion, ifnecessary interlocked. Using these techniques, selected areas in thefactory or workplace floor may be covered with panels as needed.

In addition to the foregoing, it is frequently desirable to provideelevated sections of the flooring. For example, not all persons whooperate machinery or other equipment from a standing position are of thesame height. To ensure that operators are provided the opportunity tooperate equipment at a comfortable working height, it may be desirableto raise or lower a worker's working position in relation to themachinery to minimize discomfort and fatigue. A wide variety of mats orplatform-like devices have been proposed to enable persons of varyingheights to be positioned at appropriate elevations during theperformance of operations on a machine.

As taught in U.S. Pat. No. 5,683,004, variable heights of supportstructures may be constructed from a plurality of platform members whichmay be removably stacked through the use of coupling members.Preferably, the coupling members are uniform so that any one of them maybe accommodated in sockets formed in platform members.

As known in the prior art, each coupling member comprises a cylindricalbody open at one end and closed at the other end by a transverse wall.Fixed to and extending from the wall are extensions of the body sectionin the form of a pair of projections which are spaced apart from oneanother. The overall length of each coupling member is such that whenthe body section is accommodated in a socket, the projections extendbeyond the upper surface of the associated platform a distancesufficient to engage the next adjacent platform.

Each platform has a plurality of spaced apart ribs or partitions whichdefine an open grid construction for each platform. A part of eachsocket adjacent to the upper surface of each platform is spanned by atleast one crossbar, thereby providing a grid configuration across theupper end of each socket.

In the prior art, the space between the two projections in each couplingmember corresponds substantially to the thickness of one of thecrossbars which spans the socket, thereby enabling the projections of acoupling to extend beyond the lower surface of an upper platform memberand straddle the crossbar which spans the socket of the next adjacentlower platform. Preferably, space between the two projections in eachcoupling tapers or narrows toward the free ends of the projections,thereby enabling the projections frictionally to grip the crossbar andminimize inadvertent separation of one platform from another.

The grid configurations in each platform enable any spilled liquids orsmall or other parts to fall through the platform, thereby avoiding thebuildup of liquids and/or contaminants on the upper surface of theplatform. Preferably, the transverse wall at the closed end of each ofthe body sections of the couplings also has openings therein throughwhich liquids may drain. The grid configurations of the platforms inearlier implementations of the invention were uniform, in that thethickness of the crossbars was constant, regardless of the size andshape of the platform sections. However, more recently, platformsections have been developed with higher load capabilities,necessitating thicker grid crossbars on coupling members designed forolder designs of platforms that are accordingly improperly sized toengage the grid crossbar of the newer platform sections. While it ispossible to solve this problem by substituting coupling members having alarger space between the projections, such coupling members will notprovide a suitable friction set when used with older styled platformsections having thinner grid crossbars.

Additionally, it has been learned that suitable drainage cannot beobtained using prior art devices and that a substantially larger numberof drain passageways must be incorporated.

Prior art devices are also limited in that the structural strength ofthe cylindrical wall of the coupling member has been shown to beinsufficient, and structural changes to the coupling body to improve itsstrength are required. Moreover, in order to ensure interconnection ofadjacent coupling members, it is necessary that the dimensions forstrengthening be designed in such a fashion so as to preventinterference between the projections of the coupling and the interior ofthe cylindrical portion of the adjacent coupling.

An object of the present invention is, therefore, to provide a couplingmember which will effectively interface with platforms having varyinggrid dimensions. A further object of the invention is to provide acoupling member for platform sections with the improved strength anddrainage characteristics.

These, and other objects of the invention, will be apparent from thedetailed description which herein follows.

DESCRIPTION OF THE DRAWINGS

The description herein makes reference to the accompanying drawingswherein like referenced numerals refer to like parts throughout severalviews and wherein:

FIG. 1 is a perspective view of the critical elements of the prior artshown in exploded relationship;

FIG. 2 is a perspective view of a coupling found in the prior art;

FIG. 3 is a side view of the coupling found in the prior art;

FIG. 3A is an elevational view of a coupling found in the prior art;

FIG. 4 is a plan view of a coupling found in the prior art;

FIG. 5 is a perspective view of the important components of theinvention as shown in exploded configuration;

FIG. 6 is a perspective view of the coupling of the present invention;

FIG. 7 is a side view of the coupling of the present invention;

FIG. 8 is an elevational view of a coupling as described in the presentinvention; and

FIG. 9 is a plan view of the coupling of the present invention.

DESCRIPTION OF THE PRIOR ART

With reference now to FIGS. 1, 2, 3, 3A, and 4, the prior art over whichthe present invention improves will be understood.

In the prior art, a plurality of square, rectangular, or othersuitably-shaped platforms 1, each of which has opposite end walls 2joined by opposite side walls 3 and a plurality of longitudinal andtransversely-extending ribs 4 and 5, respectively, form a grid having aplurality of spaces 6 therein. Each platform 1 preferably is molded of asuitable plastic having sufficient strength to support a person andwhich is substantially inert to oils and other liquids to which it maybe subjected in the environment of its use.

At suitably spaced intervals each platform has at its lower side acylindrical socket 7 having a smooth bore 8 and an annular wall 8 a. Thenumber and spacing of such sockets should be sufficient to enable eachplatform to be supported in a stable, horizontal position by a supportmember yet to be described. At its upper end the socket 7 is spanned bycontinuations of the ribs 4 and 5 to form a grid of crossbars 9 and 10integrally formed with the remainder of the platform. The crossbars 9and 10 span the upper end of the socket, but the opposite or lower endof the socket 7 is open. One of the crossbars, 10, extends diametricallyof the socket.

A single platform 1 may be placed in such position as to support aworker at a machine operated or attended by such worker. Such platformprovides adequate support for the worker and the open grid constructionof the platform enables any small objects or spilled liquids to passthrough the platform, rather than collect on the upper surface thereof.

Not all workers are of such height as to be able to assume acomfortable, non-tiring position alongside the machine that such workeris operating or attending. Accordingly, provision is made to enable atleast one, and preferably more, like platforms to be stacked andretained in overlying relation with one another. It is important thatthe stacked platforms be immovable relative to one another so as toavoid the possibility that a person stepping onto or leaving the stackedplatforms causes the stacked platforms to shift relative to one another.

The apparatus includes coupling means 11 for connecting adjacent,vertically stacked platforms 1 to one another. Each coupling isidentical and comprises a cylindrical body section 12 having a smoothinner bore 13, the body section 12 being open at its upper end andclosed at its lower end by a transverse wall 14. The inner surface ofthe wall has integrally formed therewith an upstanding hub 15 from whichribs 16 radiate. The hub and ribs strengthen the wall 14. To providedrainage through the coupling 11 the wall 14 has one or more drainopenings 17 formed therein.

Secured to and extending from the outer surface of the wall 14 inprolongation of the body section 12 is a pair of projections 18, each ofwhich terminates in a free end 19. Each projection 18 preferably ishollow to provide some flexibility of the projections for a purposepresently to be explained.

Each projection has adjacent its wall 14 an enlarged, outwardly arcuateportion 20 that is joined to a reduced end portion 21, the portions 20and 21 being separated by a shoulder 22. Each side of each projection 18has a flat surface 23.

Preferably, the outer surface of the body section 12 adjacent the freeend is reduced in size, as shown at 24, which facilitates insertion ofthe body section into a socket 7.

To assemble a pair of platforms 1 in overlying relation, the upperplatform is raised to enable a coupling 11 to be accommodated inselected sockets 7 of the upper platform. The overall height of the bodysection 12 preferably corresponds substantially to the height of thesocket 7 so that, when the open end of the body section 12 abuts thecrossbars 9 and 10, the projections 18 extend below the lower surface ofthe platform in which the coupling is mounted. The extent to which theprojections 18 extend beyond the lower surface of the upper platform 1is sufficient to enable the two projections to pass and straddle thediametrical crossbar 10 of the adjacent lower platform 1, the crossbar10 being accommodated in a space 25 provided between the two extensions18.

The radius on which the arcuate surface 21 of each projection is formedpreferably is less than the radius on which the socket bore 8 is formed,but the radius on which the enlarged portion 20 of each projection isformed corresponds substantially to the radius of the bore 8 of thesocket thereby enabling the enlarged portions 20 of the projections toprovide lateral stability for the associated coupling when the couplingis assembled with the platform. The flat surfaces of the projections 18enable the reduced portion of each projection to pass between parallelcrossbars 9 at the upper end of the socket 7 of the lower platform.

The height of the space 25 corresponds to the full length of eachprojection 18, thereby enabling the outer surface of the transverse wall14 at the closed end of the body section 12 to seat on the upper surfaceof the crossbar 9 and 10 which span each socket 7.

Preferably, the space 25 between the adjacent projections 18 has a widthcorresponding substantially to the thickness of the crossbar 10, buttapers toward the free ends 19 of the projections by one or two degrees.The material from which the projections is formed has sufficientresilience to enable the projections to flex, and the flexibility of theprojections is enhanced by the hollow construction thereof. The taperenables the diametrical crossbar 10 to deflect the projections away fromone another as the crossbar 10 moves into the space 25, and theresilience of the projections enables the crossbar to be gripped by theprojections when the crossbar 10 is accommodated between theprojections, thereby minimizing the likelihood of inadvertent separationof the coupling from the lower platform 1.

A ground engagable support is provided for each socket 7 of the lowerplatform 1. Such support as indicated at 26 and comprises a hollowcylinder 27 open at its upper end and provided at its lower end with arubbery or other suitable cap 28 which provides an anti-skid surface forthe lower end of the cylinder 27. The overall height of the cylinder 27is such that the latter may be accommodated in any one of the sockets 7with its upper end abutting the crossbars 9 and 10 and with its non-skidcap 28 projecting slightly beyond the lower surface of the lowerplatform 1. The supports 26 enable the lowermost platform to occupy ahorizontal position.

The length and width of each platform should be sufficient to enable itto provide adequate space in which a person may stand and move to theextent necessary to operate or attend a particular machine.

DESCRIPTION OF THE PREFERRED EMBODIMENT

The disclosed prior art performs well; however, it has been learned thatimproved performance of the platform elements can be achieved by makingcertain dimensional changes to the platform ribs and that the system, asa whole, will benefit from increasing drainage performance in certainindustrial environments.

The improvement of the present invention; therefore, is described indetail below and depicted in FIGS. 5-9.

The presently preferred embodiment of the invention is illustrated inthe drawings and comprises a plurality of square, rectangular, or othersuitably shaped platforms 101 each of which has opposite end walls 102joined by opposite side walls 103 and a plurality of longitudinally andtransversely extending ribs 104 and 105, respectively, which form a gridhaving a plurality of spaces 106 therein. Each platform 101 preferablyis molded of a suitable plastic having sufficient strength to support aperson and which is substantially inert to oils and other liquids towhich it may be subjected in the environment of its use.

At suitably spaced intervals each platform has at its lower side acylindrical socket 107 having a bore 108 and an annular wall 108 a. Thenumber and spacing of such sockets should be sufficient to enable eachplatform to be supported in a stable, horizontal position by a supportmember yet to be described. At its upper end the socket 107 is spannedby continuations of the ribs 104 and 105 to form a grid of crossbars 109and 110 integrally formed with the remainder of the platform. Thecrossbars 109 and 110 span the upper end of the socket, but the oppositeor lower end of the socket 107 is open. One of the crossbars, 110,extends diametrically of the socket.

A single platform 101 may be placed in such position as to support aworker at a machine operated or attended by such worker. Such platformprovides adequate support for the worker and the open grid constructionof the platform enables any small objects or spilled liquids to passthrough the platform, rather than collect on the upper surface thereof.

Not all workers are of such height as to be able to assume acomfortable, non-tiring position alongside the machine that such workeris operating or attending. Accordingly, provision is made to enable atleast one, and preferably more, like platforms to be stacked andretained in overlying relation with one another. It is important thatthe stacked platforms be immovable relative to one another so as toavoid the possibility that a person stepping onto or leaving the stackedplatforms causes the stacked platforms to shift relative to one another.

The apparatus includes coupling means 111 for connecting adjacent,vertically stacked platforms 101 to one another. Each coupling isidentical and comprises a cylindrical body section 112 having a smoothinner bore 113, the body section 112 being open at its upper end andclosed at its lower end by a transverse wall 114. The inner surface ofthe wall has integrally formed therewith an upstanding hub 115 fromwhich ribs 116 radiate. The hub and ribs strengthen the wall 114. Toprovide drainage through the coupling 111 the wall 114 has one or moredrain openings 117 formed therein.

Secured to and extending from the outer surface of the wall 114 inprolongation of the body section 112 is a pair of projections 118, eachof which terminates in a free end 119. Each projection 118 preferably ishollow to provide some flexibility of the projections for a purposepresently to be explained.

Each projection has adjacent its wall 114 an enlarged, outwardly arcuateportion 120 that is joined to a reduced end portion 121, the portions120 and 121 being separated by a shoulder 122. Each side of eachprojection 118 has a flat surface 123.

Preferably, the outer surface of the body section 112 is tapered, sothat the diameter of the body section 112 nearest its upper end 124 issmaller than the diameter near the closed end transverse wall 114. Thisconfiguration facilities frictional engagement between the outercylindrical circumference of body section 112 and socket 107.

To assemble a pair of platforms 1 in overlying relation, the upperplatform is raised to enable a coupling 111 to be accommodated inselected sockets 107 of the upper platform. The overall height of thebody section 112 preferably corresponds substantially to the height ofthe socket 107 so that, when the open end of the body section 112 abutsthe crossbars 109 and 110, the projections 118 extend below the lowersurface of the platform in which the coupling is mounted. The extent towhich the projections 118 extend beyond the lower surface of the upperplatform 101 is sufficient to enable the two projections to pass andstraddle the diametrical crossbar 110 of the adjacent lower platform101, the crossbar 110 being accommodated in a space 125 provided betweenthe two extensions 118.

The height of the space 125 corresponds to the full length of eachprojection 118, thereby enabling the outer surface of the transversewall 114 at the closed end of the body section 112 to seat on the uppersurface of the crossbar 109 and 110 which span each socket 107.

It will be appreciated that the distance between the projections 118 ofthe coupling 111 and the dimensions of crossbars 109 and 110 will enablethe coupling 111 to remain immovably secured to the platform 101.Platforms 101, however, may be manufactured with varying dimensions ofgrid width and spacing. In some applications, diametrical crossbar 110is characterized by a maximum width of 0.35 inches of the space 125between adjacent projections 118 of coupler 111, accordingly, isdesigned to have a complimentary dimensions at free end 119, and anominally smaller dimension closer to transverse wall 114. Accordingly,when the projections 118 of the coupling 111 are inserted to spaces 106,to straddle crossbar 110, the frictional forces exerted by projections118 against crossbar 110 increase since dimension “A¹” as shown in FIG.8 is nominally smaller than the dimension “A” shown in the same figure.As a result, when coupling 111 is fully inserted into platform 101 byengagement of projections 118 against rib 110, a secure frictionalengagement between the coupling and the platform is achieved. In thisapplication the invention, however, flat surfaces 123 of projections 118are not brought into contact with crossbars 109. This is becausedimension B as shown in FIG. 7 is specifically selected to ensure thatthe width of projections 118 between opposing flat surfaces 123 issmaller in dimension than the opening formed between two parallelcrossbars 109.

Preferably, the space 125 between the adjacent projections 118 has awidth corresponding substantially to the thickness of the crossbar 110,but tapers toward the free ends 119 of the projections by one or twodegrees. The material from which the projections is formed hassufficient resilience to enable the projections to flex, and theflexibility of the projections is enhanced by the hollow constructionthereof. The taper enables the diametrical crossbar 110 to deflect theprojections away from one another as the crossbar 110 moves into thespace 125, and the resilience of the projections enables the crossbar tobe gripped by the projections when the crossbar 110 is accommodatedbetween the projections, thereby minimizing the likelihood ofinadvertent separation of the coupling from the lower platform 101.

A second version of platform 101 incorporates narrower crossbars 109 and110. In this version of the platform, crossbars 109 and 110 have a widthof approximately 0.325 inches. The dimension between parallel crossbars109 is nominally 0.85 inches, which is approximately 0.05 inches lessthan the inter-crossbar dimension of the first type of platform 101.With reference now to FIG. 7, it will be appreciated that by makingdimension B 0.825 inches or slightly less, and tapering the projections118 so that dimension B¹ is 0.825 inches or slightly larger, that africtional fit can be achieved between flat surfaces 123 and crossbars109 when coupling 111 is used with the second style of platform 101.

In this fashion, a single coupling is disclosed which serves to coupleboth styles of platform 101. It is preferred that a ground engageablesupport be provided for each socket 107 of the lower platform 101. Suchsupport as indicated at 126 and comprises a hollow cylinder 127 open atits upper end and provided at its lower end with a rubbery or othersuitable cap 128 which provides an anti-skid surface for the lower endof the cylinder 127. The overall height of the cylinder 127 is such thatthe latter may be accommodated in any one of the sockets 107 with itsupper end abutting the crossbars 109 and 110 and with its non-skid cap128 projecting slightly beyond the lower surface of the lower platform101. The supports 126 enable the lowermost platform to occupy ahorizontal position.

The length and width of each platform should be sufficient to enable itto provide adequate space in which a person may stand and move to theextent necessary to operate or attend a particular machine. It ispossible, of course, to have a lowermost platform of relatively greatlength so that upper platforms of shorter length may be supported atopthe lower platform with spaces between the shorter platforms. It also ispossible for the areas of upper and lower platforms to be the same.

It will be appreciated that, in the present invention, the dimensionbetween the outer surfaces of the first stepped sections 120 ofprojections 118, being dimension C is selected to be substantially equalto the diameter of the inner bore 113, thereby permitting one coupling111 to be nestable within the inner bore 113 of an adjacent coupling111. In other words, projections 118 are fully insertable into the innerbore 113 of an identical coupling 111. Further, diametrical dimension Dmeasured between the outermost surfaces of second step section 121corresponds substantially to the inner diametrical bore dimension ofsupport 126. The dimension E of first stepped section 120 is selected tobe substantially equal to the thickness of crossbars 109 and 110, sothat when coupling 111 is inserted into socket 107 of platform 101, onlythe second step section 121 of legs 118 projects into the bore 108. Inthis fashion, the outer circumference of support 126 frictionallyengages the bore 108, while the inner bore of support 126 accommodatessecond stop section 121 of legs 118, thereby adding to the security andstability of the assembly. Dimension D is also smaller than thediametrical dimension of the inner bore 113, thereby permitting coupling111 to be inserted from the underside of platform 101 into bore 107,thereby facilitating the stacking of multiple platforms 110 utilizingmultiple couplings 111.

The disclosed embodiment is representative of the presently preferredform of the invention, but is intended to be illustrative rather thandefinitive thereof. The invention is defined in the claims.

1. A coupler for stackably interconnecting two classes of platforms,each platform having at least one vertically extending socket, eachsocket having at least one diametrical cross member and at least twotransverse cross members perpendicular to said diametrical cross member,the said at least one diametrical cross member of a first class ofplatforms having a first thickness and said at least two transversecross members of said first class of platforms being separated by afirst distance; The said diametrical cross section of a second class ofplatforms having a second thickness and said at least two transversecross members of said second class of platforms being separated by asecond distance, said coupler comprising a body section having a crosssectional configuration corresponding to that of said socket and furthercomprising a pair of projections separated by a space, each of said pairof projections having a width, said space being greater than said firstthickness of said diametrical cross member of said first class ofplatforms and said space being substantially equal to said secondthickness of said diametrical cross member of said second class ofplatforms.
 2. The invention of claim 1, wherein said width of saidprojections is substantially equal to said first distance separatingsaid transverse cross members.
 3. The invention of claim 1, wherein saidwidth of said projections is substantially equal to said seconddistance.
 4. The invention of claim 1, wherein said space tapers.
 5. Theinvention of claim 1, which further comprises a plurality of ribspositioned within an internal cavity in said coupler.
 6. The inventionof claim 1, wherein each said cavity further comprises a plurality ofdrainage openings.